Means for controlling electric heaters.



No. 676,309. Patented luna ll, l90l.

E. E. sou). NEANS FOR CONTROLLING ELECTRIC HEATERS.

(Applicltion filed Nov. 9. 1899.)

(No Nodal.) 2 Sheets-Shoat I.

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' INVENTOR; WITNESSES- 5M @24 4 M 5 By Attorneys,

No. 676,309. Patented .Iune n, 1901. E. E. sow.

MEANS FORGOILIROLEING- ELECTRIC HEATERS.

(Application mad .Nov. 9, 1899.) (No Model.) 2 Sheets$heat 2.

INVENTOR:

WITNESSES:

M Noun mun cu. momuma. wunmorm. n. cy

UNITED STATES PATENT OFFICE.

\ EDWARD E. GOLD, OF NEW YORK, N. Y.

MEANS FOR CONTROLLING ELECTRIC HEATERS.

SPECIFICATION forming part of Letters Patent No. 676,309, dated June 11,1901.

Original application filed March 10,1897, Serial No. 626,750.

T0 at whom it may concern.-

Be it known that I, EDWARD E. GOLD, a citizen of the United States,residing in the city, county, and State of New York, have inventedcertain new and useful Improvements in Means for Controlling ElectricHeaters, of which the following is a specification.

The present application is a division of my application filed March 10,1897, Serial No. 626,750, patented December 12, 1899, No. 639,170.

The present invention has been patented in Great Britain, No. 7,318,dated April 4, 1896; in Austria, No. LG/ 2,643, dated July 2, 1896, andin France, No. 268,222, dated June 26, 1897. v p

This invention relates to means for controlling electric heaters havinga multipicity of coils or resistant conductors connected in parallel. Inheaters of this type the degree of heat is controlled by varying thenumber of coils or resistances in circuit. With a uniform difference ofpotentials at the main conductors or leads and with coils of equalresistance the amount of he'at generated would be in exact proportion tothe number of coils in circuit-a theoretical ratio which is approximatedin practice.

My invention will be best understood with reference to the accompanyingdrawings, wherein- I Figure 1 is adiagrammatic view showinga switch orcontroller and threeheaters with marked, respectively, 1, 2, and 3.

their circuit connections, the controller being adapted for heatershaving each two unequal heating elements. Fig. 2 is a sectionalelevation of the electrical parts or elements of the switchBshown inFig. 1. Fig. 3isasimilar elevation of a modifiedcoustruction of switch.Figs. 4 and 5 show my system as adapted for heaters having'three heatingelements.

In Fig.1,let A A designate the electric heaters of, for example, astreet railway car, each heater consisting of three coils, (or otherresistant conductors,) which are The dotted rectangleinclosing the coilsmay be taken to indicate the casing of the heater. The particularconstruction of the heater is quite immaterial to my present invention;

' but a suitable construction is that set forth Divided and thisapplication-filed November 9, 1899. Serial (No model.) v

in my application, Serial No. 586,396, filed April 6, 1896, or my laterapplication, Serial for instance,No. 1 in Fig. 2-is connected alone orby itself with the conducting-wire a, which leads to and from it. Theother two coils,

Nos. 2 and 3, are connected together at their terminals, (so thattogether they constitute a coil or heater element of greaterheat-generating capacity than thesingle coil 1,) and the intermediateconnection is joined to a conducting-wire 17. Thus fora three-coilheater,

there are only two conductingwires a and 1). These wires lead at one endto the switch or controller 13, which is connected to one of theleads'O, and at the other end the wires conv meet with the opposite leador main conductor D, Fig. 1. Between the controller B and the oppositelead D there is introduced a series or plurality of electric heaterswith their coils No. 1 all connected in series on the wire a and theircoils 2 and 3 connected in parallel series on the wire b-that is to say,the successive groups each composed of the coils 2 and 3, joined inparallel with each other, are connected serially on the wire, as clearlyshown in Fig. 1. Hence for a succession of three-coil heaters only twowires are employed between the controller and all the heaters of theseries.

The conditions essential to the switch or controller B may be bestunderstood from the modification, Fig.3, which shows an ordinaryhand-switch, the conducting-arm c of which is connected with one of themain leads'O,

' and the contacts 61 d of which are connected with the wires a b. Inposition 0 the arm rests on a blind contact, so that the circuit isbroken, the heaters being thus shut 01?. In position 1 the arm rests onthe first contact d, and thereby connects with wire a, so that thecurrent traverses coil No. 1. In position No, 2 the arm rests on thesecond contact 01', which communicates through the wire I) with thecoils 2 and 3. In position No. 3 the arm rests on a double contact (1which is com nected by conductors -(shown =in dotted lines) to theothercontacts, so that in this position one coil of the-heater and the.lowest degree of heat is generated. Imposition No. 2 the currenttraverses two coils of the heater and a greater'degree of heat isgenerated. Inposition No.3 the current traversesall three of theheater-coils-and' the maximum degree of heat is generated. It is anadvantage peculiar to this mode of connecting the coils of electricheaters in connection with a proper switch for. controlling them in. themanner just described that the heating service is in maintained at ahigh temperature.

ing the variations in weather conditions to be such that the minimum,medium, and maximum degrees of heat are required each during aboutone-third of the time, as is ap a measure, equally apportioned betweenthe three coils of the heater, since in the mildest weatheri'n which theheater is in usecoil No. l is alone used, whilein'weathera little colderthis coil 'isthrown out of useJand coils Nos.

2 and. 3 are alone used. The system upon which, my invention is directlyan improve ment is the one in which with the minimum.

degree of heat coil No. 1 is in use, with the medium degree'of heatcoils Nos. 1 and 2 are muse, and'withthe maximum degree of heat coilsNos. 1, 2, and 3 are employed, so that underall.eonditiOnswheneVer anyheat is turned on atalleoil No. 1 is in service and proximately the casein practice, it follows thateoil'No. 1 has three times the extent ofservice of coilNo. 3 and coil No. 2 twice the. extent of servlce of coilNo. 3, and as in practice there is some inevitableoxidation or otherdeterioration of the coilsit follows that coi'l No.1 will lastonly'one-third as long as coilfNo. '3 and only one-half as long as coil.No. 2. This inequality in the lifetimeof the three coils is prevented bymy invention,'

which insures that coil No. 1 shall be in servdegree, so that assumingan equal time interval forthe useo'f each of the three degrees'andassuming that the coils are exactly alike .there E results an equalityof endurance or equal 1ife-: time for the three coils. The prior systemreferred. to also demands the use of three'wires, one for each coil,which by my system is rev ducedto two Wires, thereby simplifying theconnections and cheapening the installation heaters (here lettered A).is provided with five coils instead of three.

of'the heaters.

I The simple switch shown in Fig. 3 requires the switch. To this end itis desirable to em.-

Assumeases ploy some one of the well-known; construe tions ofsnap-switch in which the switch-arm or circuit-controlling part is movedso quickly as to prevent the formation of an arc. Numerous constructionsof these switches are well known and in common use. In my application,Serial No.626,750, filed March 10, 1897, Patent No. 639,170, datedDecember 12, 1899, .(of which application my present application is adi-vision,) I have shown and claimed a construction of snap-switchadapted to carry out the principle and mode of controlling omitting themechanical snap-action device.

In Fig. 2 F shows a disk which is caused to. executearapidquarterfrevo'lution each time the knob of the switch is turned.This-disk carries three cond noting-'blocks n n,-of metal. 7 I Astheconducting-blocks arecarried aroundby. the movements of the disk theirinner ends rub againsta conducting-strip 19. Outside of the disk areplacedequidistant spring 1 contacts qq g "tor O is connected to thecontact q, the wire The main lead or conduca is connected to theopposite contact qiand the wire I) to the intermediate contact 1. Theresult of this arrangement is that ofth-e four stopping positions of thedisk F in the first there is no block n in contact with the initialcontact-strip q, and consequently no current can pass to the heater. Inthe next position two blocks touch, respectively, the contacts q g sothat the current passes by wire a to coil No. 1 of the heater. In thenext forward movement the switch is brought to the position shown inFig. 2, wherein two blocks touch the contacts qand q, so that v thecurrent passes to the coils Nos. 2 and3 of the heater. In the fourthpositionallthree blocks n are in contact with all three :contact-pieces,so that thecurrent divides, passin gthrough all three coils of theheater. For a more full description of the mode of construction andoperationof a switch of this character (which is not in itself claimedin my present application)I refer to my said Patent No. 639,170.

Ordinarily in electricheating it is not necessary or desirable toprovide more than three different gradations of heat. Hence a threecoilheater is suflioient for every ordinary requireinent of practice; but.if heaters of 'a greater number of. gradations are required myinvention may be extended in its scope to servefor the control of such.heaters One example of such development of my invention is shown in Fig.4, where each of the Nos. 2 and 3 ,are joined. at their ends and.

connected with wire 6,. and coils 4 and 5 are joined together at theirendsand connect IIO ina third wire b. The switch here shown is forclearness of the same order asthat shown in Fig. 3, difiering therefromonly in that a greater number of contacts are provided in order toestablish the greater number of combinationsrequired for controlling afive-coil switch. In position No. 1 the current traverses only wire aand coil No. 1.

In position No. 2 it traverses only wire band coils Nos. 2 and 3. Inposition No. 3 the arm rests on two contacts,-one of which is elec-,

trically connected by wire 11 with the'first contact and wire a and theother of which is connected by a wire 12 with the second contact andwire I), so that thecurrent traverses both these wires and the threecoils 1, 2, and 3. In position No. 4: the arm rests on two contacts, oneof which is connected by wire 12 with the second contact and the wire I)and only'with wire a and coil No. 1.

the other of which is in connection with the wire 6, so that the currenttraverses four coils Nos. 2, 3, 4, and 5, and, finally, in position 5the arm rests upon three contacts, two of which are connected by wires11 and 12 with wires 01, and b and the third of which is connected bywire 13 with wire b", so that in this position the current divides andtraverses all-five coils.

In Fig. 5 the same principle is shown as applied to a six-coil heater.Coil No. 1 is connected with wire a, as before. OoilsNos. 2 and 3 areconnected in wire I), as before. Coils 4, 5, and 6 are joined togetherat their ends and connected in the third wire I). The switch differsonly in the arrangement of the contacts and intervening electricconnections. In position No. l the switch-arm connects In position 2 itconnects only with wire I and coils 2 and 3. In position 3 the arm restson two contacts, which connect, through wires 11 and 12, with the firstand second contacts and wires a and b, so that the current traverses allthreecoils 1, 2, and 3. In position 4 the arm rests on two contact-s,one of which connects bywire 11 with wire C6 and coil No. 1 and theother of which connects with wire I) and coils 4, 5, and 6, so that inthis position four coils are in circuit. In position 5 the arm restsontwo contacts, one of which con-' nects by Wire 12 with wire I) and coils2 and 3 and the other of which connects by wire 13 with wire I) andcoils 4,5, and 6, so that in this position five coils are in circuit,and,

her, the first group, for example, containing one coil and the'secondgroup containing two coils, and if additional coils exist they are putin an additional group, which ina fivecoil heater contains the tworemaining coils of coils and requiring the arrangement of a fourthgroup, or even more; but this would transcend all requirements ofordinary practice.

It is not necessarily essential to my invention that the heat generatingor resistant elements of the heaters should be coils of wire, as otherresistances might be substituted; nor is it necessarily essential thattwo or more such coils or resistances should be grouped in parallel toconstitute the heating element of double heat-generating capacity, asanyother known arrangement or proportion bywhich the branch circuit a maycontain a minor heat generating element (of which the coil 1 is anexample) and the branch 5 a major heat-ge'nerating-element (of which thecoils 2 and 3 are an example) is within the principle of my invention.

I claim as 'my invention the following-defined novel features,substantially as hereinbefore specified, namely:

1. The combination of a succession of electric heaters, each includingheating elements of unequal heat generating capacity, two branchcircuits traversing the successive heaters, the one including the minorheating elements thereof, and the other including the major heatingelements thereof, and a switch at the junction of said branches with themain circuit, movable to 'as many difierent positions as the number ofdegrees of heat desired, in one position connecting the main circuitwith only one branch circuit, in another position with only the otherbranch, and in a third position with both branches.

2. The combination of a succession of electric heaters A A, eachincluding heating elements of unequal heat-generating capacity, twobranch circuits at b traversing the successive heaters, the oneincluding the minor heating elements thereof, and the other includingthe major heating elements thereof, said branches connected at one endpermanently to one circuit-wire D, and at the other end connectedthrough a switch'B with the other ci rcuit-wire C, and said switchmovable to as many different positions as the number of degrees of heatdesired, in one position connecting the main circuit with only onebranch circuit, in another position with only the other branch, and in athird position with both branches, to the eifect set forth. I

3. The combination of a succession of electric heaters, each includingheating elements of unequal heat-generating capacity, consisting ofresistant'coils of naked wire exposed I to circulation of air, the minorelements comprising a single coil and the major elements comprising aplurality of coils grouped in parallel, two branch circuit-wirestraversing too the successive heaters, one wire connecting serially thecoils constituting the minor heat ing elements .thereof,and the otherwire-connecting serially the groupsof coils-nonstitut- 1 ing-the majorheating elements thereof, and a switch at the junction of said branches;with the main circuit, movable-to-as many different positionsas thenumber-of degrees of heat desired, in one position connecting the maincircuitvwit-h only one branchcircuit, Z p

heaters suitably disposed for heating'a car inlanotherposition withonlythe othergbranch,

and in a third position with both lor'z mchesti V 1 Ielementsofunequalheat-generatingcapacity,

to the effect set fforth. v

4. The combinationof -a successioniof eleci' trio heaters,eachincludingheating elements. of unequal heat generating capacity, twofbranch circuits traversing the successive; heaters, the oneincluding-the minor heating elements thereofland the;otherincludingthe 1majior heating elementsthereof, and a switch atthe'junctionof saidbranches with-the main circuit, movable to as many differentpositionsxas the number of degrees-of heatdesired, i inone positionconnecting the main-circuit with only one branch circuit, in-anotherpo-I 5 i degreeofheat, ,ort-solel-ythrou-ghthe branch thirdposition withbothbranchesnthe switch connections being so arranged thata differ-: entdegree of heatis obtainedforeachof the 1' {giving the maximum or thirddegree of heat.

sition with only the other branch,,and in a difterent positions ofthe-switch.

v5 The-combinationofasuccessionof eleci trio .-heaters,,eachincludingheatingelements of unequal heat-generating capacity, two branchcircuits traversing the successive f heaters, theoneincluding theminor-heating I elements thereof, and the other including'themajoriheating elementsthereof, a switch at; a the junctioniof saidbranches with themain 3 switch connections :being soarranged that a 5continuous operationof said'contacmmaking inemberproducessthegdifierent*degreesofheat falwaysin thesame-or'der vofsuccession.

circuit, axco'n-tact making :niem'ber in said switch pnio ahiertc asmanyidifterenmpositiens i as the n umber-of degrees of ,heatdesired,ithe

6. The comb'inati'on-ofwa serieszof electric or apartment, each rheaterincluding heating the major element having approximately l twice :thecapacity of the;nrinor=element,"=two branch circu itsextending throughthe .car or apartmentandtrawersing thesuccessi.ve-heat ers, the onebranch including in seriesthe minor heatingelementsrthereof,andtheYother including the major heatinggelements thereof,

with circ nit-closing n-cans adapted at :will to iopeniorjr-closeleitherof saidhra-nch circuits,

whereby the current may '{be passed solely through the branchcontainingthem'inoriheatling elements forgiving theminim-um .or first containingthetmajorheatingielementsforg-iv- ;iug., a-n intermediatetonseconddegreeof heat,

orsimultaneously through ibothjbranchesfor witnesses.

Witnesses:

In witness whereof 'lahave hereuntosigned my 'name in the presence-oftwosubscribing EDWARD co n.

' ARTHUR G. FRASER, :F'RED WHITE.

